Drinking alcohol while pregnant is common in UK, Ireland, and Australasia, according to UK researchers, sparking concerns from midwives.
The trend is evident across all social strata but expectant mothers are significantly more likely to drink if they also smoke, said the authors of the international study.
“Alcohol use during pregnancy is highly prevalent, and… gestational alcohol exposure may occur in over 75% of pregnancies in the UK and Ireland”
Their study of almost 18,000 women found drinking alcohol while pregnant ranged from 20% to 80% among those questioned in the UK, Ireland, Australia and New Zealand.
The researchers based their findings on an analysis of data from three studies – the Growing up in Ireland (GUI) study; the Screening for Pregnancy Endpoints (SCOPE) study and the Pregnancy Risk Assessment Monitoring System (PRAMS).
The studies variously assessed the amount and type of alcohol drunk before and during pregnancy and involved 17,244 women who gave birth in the UK, Ireland, Australia and New Zealand.
The researcher’s new analysis, published online in the journal BMJ Open, indicated a high prevalence of drinking, including binge drinking, among pregnant women.
The prevalence of drinking alcohol ranged from 20% to 80% in Ireland, and from 40% to 80% in the UK, Australia, and New Zealand.
The amount of alcohol drunk varied across the three studies included in the analysis.
Between 15% and 70% of the women said that they had drunk 1-2 units a week during the first trimester of their pregnancy. But the number of reported units dropped substantially in all countries between the first and second trimester, as did binge drinking.
“Where midwives are encouraging women to quit smoking they should also ask about alcohol consumption”
The findings indicated that the prevalence of drinking while pregnant was generally evident across all social strata, but several factors were associated with a heightened or lowered risk of alcohol consumption.
Compared with white women, those of other ethnicities were less likely to drink alcohol while pregnant.
A higher level of education, having other children, and being overweight/obese were also associated with a lower likelihood of drinking while pregnant.
The strongest and most consistent predictor of a heightened risk of drinking during pregnancy across all three studies was smoking. Smokers were 17-50% more likely to drink while pregnant.
The researchers suggested gestational alcohol exposure may occur in over 75% of pregnancies in the UK and Ireland.
But they said most of these women consumed alcohol at very low levels and the number of pregnant women who drank heavily in the three studies was small.
“Since most women who consume alcohol do so at lower levels where the offspring growth and development effects are less well understood [than at higher levels], the widespread consumption of even low levels of alcohol during pregnancy is a significant public health concern,” they warned.
Louise Silverton, director for midwifery at the Royal College of Midwives, said: “The overall number of pregnant women who continue to drink alcohol during pregnancy is very concerning, as there is no evidence that any level of consumption is safe for the growing baby.
“Where midwives are encouraging women to quit smoking they should also ask about alcohol consumption and encourage abstinence during pregnancy,” she said.
She added: “Providing pregnant women with more support and up-to-date information is paramount and advising women on the potential consequences of alcohol consumption and smoking during pregnancy should be of utmost importance to all midwives, GP’s and maternity support workers.”